Testosterone is actually a steroid, but the term steroid is just a chemical classification of certain fat-soluble organic compounds, many of which are found naturally in the human body. They’re responsible for having a whole slew of physiological effects ranging from tissue growth, reproductive development, inflammation, immune response, and even salt and water balance. Examples include estrogen and, of course, testosterone. Testosterone is responsible for the development of secondary sex characteristics like broader shoulders, a deeper voice, development of sexual organs, facial hair, and most of the physical characteristics that distinguish men from women. When men get older and their testosterone levels drop, testosterone replacement therapy is often prescribed to reverse many of the effects of aging and to restore confidence, libido, and a more youthful, energetic feeling. Of course, when most non-medical people refer to steroids, they’re referring to anabolicsteroids, which are typically used for cosmetic performance or physical performance reasons (like building muscle, burning fat, or enhancing athletic ability). It’s true that all anabolic steroids are synthetic variations of naturally occurring testosterone, but as mentioned, they’re used for non-health reasons and aren’t suitable for testosterone replacement therapy. Many have unpredictable side effects and they’re almost always used in extremely large, potentially dangerous doses. So yes, testosterone is a steroid, but it‘s a naturally occurring one that’s vital to a healthy functioning body.